Automatic cut-off governor



3 Sheets-Sheet 1.

(No Model.)

J. B. STANWOOD. AUTOMATIC GUT-OFF GOVERNOR.

No. 307,501. Patented Nov. 4, 1884.

(No Model.) 3 Sheets-Sheet 2.

J. 13. STANWOOD-j.

AUTOMATIG GUT-OFF GOVERNOR. No. 307,501; Patented Nov. 4, 1884.

3 Sheets-fibeet 3.

J. B. ST A NWQOD.

AUTOMATIC GUT-OFF GOVERNOR;

Patented Nov, 4,1884.

Nrrn STATES tries.

AUTOMATIC CUT-=OFF GOVERNOR.

sPncIPIcArroN forming part of Letters Patent No. 307,501, dated November t, 1884-.

Application filed May 28,1884. (No model.)

To all whom it may concern.-

Be it known that I, JAMES B. STANWOOD, a citizen of the UnitedStates, residing at Cincinnati, Ohio, have invented new and useful Improvements in Automatic Out-Off Governors, of which the following is a specification.

My invention relates to that class of governors for steam-engines ordinarily denominated automatic cutoff governors, which, by means of the rotation of the main shaft, control the eccentricity of the valve-mover, and thus regulate the travel of the slidevalve and the admission of steam to the piston; and it consists in the construction and arrange ment of apparatus, as hereinafter fully de scribed and illustrated.

In the drawings herewith, Figure l is a per spective elevation of my improved governor complete; Fig. 2, a front elevation of the same from the pulley side; Fig. 3, a detail view of one of the bell-crank levers, showing the short arm and bearing block; Fig. l, a detail crosssection of the jaw end of one of the bellcrank levers, showing the construction and relation of the arc-bar and sliding yoke. Fig. 5 is a detail cross-section taken longitudinally through the arc-bar and across the cross-head and its guides; Fig. 6, a detail cross-section through the spring, showing its construction and relation to the bell-crank levers; and Fig. 7, a detached perspective view of one of thebellcrank levers.

In the drawings, A designates a pulley attached to the main shaft of the engine, and may be used as a band-pulley for the transmission ,of power. To the pulley is attached myimproved governor, consisting, essentially, of a supporting-frame secured to and rotating with the shaft, weighted lever fulcrumed in the frame and acting centrifugally, and by such action controlling the relative eccentricity of the valve-mover through intervening mechanism.

The frame B, with which the operative parts of the governor are connected, is a U-shaped open frame, having parallel sides, and lugs a projecting laterally from its sides below. Between the lugs at each side of the frame are pivoted bell-crank levers, whose long arms d rise outside of and parallel with the frame. terminating in heads D, constituting the weights, which, by the rotation ofthe pulley, swing outward upon their pivots through the influence of centrifugal force, as indicated by theirposition in Fig. 2. The shorter arms d of the bell-cranks extend through suitable openings Within the frame, and rest beneath a spiral spring, S, held by a bolt secured in the bottom of the frame and passing centrally between the ends of the lever-arms d and through the spring S. The spring is secured between a fixed cupshaped'head, 0, upon the upper end of the bolt 8, and-a similar-shaped sliding head, 0, centered upon the bolt, the spring acting by compression against the former as an abutment. The arms (1 of the levers cX- tend inward beneath the sliding head e, as indicated in Fig. 6, the bearing-contacts being provided with steel or gun-metal facing-blocks cl d", the arrangement being such that the centrifugal action of the weights D, carrying the arms (Z outward, is resisted by the expansive action of the spring upon the short arms cl, which normally holds the weighted arms closed inward, as shown in Fig. 1. The weighted heads D of the arms d are slotted to form jaws, between which an eccentric arcbar, G, passing through the frame 13 through openings in the sides, permitting a vertical reciprocation of the arc-bar, is arranged, held in sliding yoke-boxes a, pivoted in the jaws of the head D. The curvature of the arc-bar G is in such eccentric relation to the center of the arms (I that in their outward oscillation by centrifugal force the arc-bar is carried upward by a cam movement and drawn downward by the inward closing of the arms under the influence of the spring S.

Centrally to the side of the arc-bar is bolted a crosshead, E, arranged to embrace and slide vertically upon the outer edges, b, of the frame B, these edges being planed true and formed as parallel guides for the cross-head, the latter being provided with an elongated central slot, permitting its vertical movement unimpeded by shaft A, which passes through it. To the outside of the cross-head is bolted a ring or annular flange, forming the valve-mover,peripherally grooved or ribbed to receive the ordinary yoke connections for operating the side valve. The ring F also surrounds the shaft A, and is arranged upon the cross-head in such relation as to be moved with it by the centrifugal action of the arms 01 from its position of greatest eccentricity with the shaft to a position of minimum eccentricity therewith, so that in excessive speed of rotation of the shaft the valve-mover is carried toward a concentric position and the travel of the valve correspondingly reduced.

In order to secure a perfectly uniform joint action of the arms d, I provide an intermeshing segment-gear, ff, the corresponding elements of which are secured upon the pivotal axes g of the bell-cranks, respectively, meshing together and thus compelling a joint and uniform action. A weight, W', is secured in the upper end of the frame B as a counterbalance to the other parts of the governor,,so that-its own center of gravity shall coincide approximately with the shaft-axis.

The operation is as follows: The weights D, being carried apart by the action of centrifugal force in the rotation of the shaft, act as ca'ms to force the arc-bar O upward, carrying the cross-head E and its attached valve-moving ring, the latter by such movement being brought into a position' more nearly concentric'with the shaft. The eccentricity of the ring being thus lessened,the travel of the valve is correspondingly reduced. IVhen the speed of the engine is reduced below the determined point, the spring S, acting against the lessened centrifugal force of the weights D, closes them together, thereby forcing the arc-bar downward, carrying the cross-head, and increasing the eccentricity of the valve-mover and the travel of the valve. By this means the movement of the engine is regulated in both conditions produced by an increase or diminution of the load, and the quantity of steam admitted to the piston through the ordinary valve-ports is governed.

- -For the spring S, arranged as shown, two

springs may be employed attached directly to the long arms (1, and the short arms may be dispensed with; but the construction shown is preferred. A straight bar may be employed instead of the curved arc-bar, also; but, the curved form is preferred, the arcs being at each side eccentric to the centers of pivotal oscillation of the arms in such slight degree asto render the action of the arms upon the arc-bar exceedingly powerful, but rendering a reverse action due to any resistance of the parts impossible.

I claim as my invention and desireto secure by Letters Patent- 1. In a steam-engine governor of the kind described, the combination of two weighted 6o arms pivoted upon a suitable frame at the same side of the shaft, and swinging centrifugally outward therefrom to opposite directions, with a movable cam-bar secured to a cross-head carrying the valve-mover, erated by'such centrifugal movement of the arms to vary the eccentricity of the valvemover, substantially as set forth.

2. In an automatic cut-off governor, the

combination, with the supporting frame and the movable cam bar carrying the valvemover, of the bell-crank arms pivoted in the frame, as shown, to swing outward from the shaft and act as a cam upon the movable bar,

and the spring arranged, as shown, to act upon the bell-cranksin opposition to centrifugal force, substantially as set forth.

3. In an automatic cut-off governor, in combination with movable cam-bar carrying the valve-mover, the bell-crank arms provided 30 with intermeshing gear compelling their simultaneous action, substantially as set forth. at. In an automatic cut-off governor, the cambar 0, in combination with arms d, provided with the heads D, and the pivoted yoke-boxes a, 8 5

substantially as and for the purpose specified.

5. In an automatic cut-off governor, the cambar 0, in combination with the arms (1, provided with the heads D, and thepivoted yokeboxes at, substantially as and for the purpose o specified.

6. In an automatic cut-off governor, the

combination of the frame B and the spring S,

arranged within the frame above and acting upon the' short arms d of the bell-cranks, con- 9 5 structed and arranged substantially as and for the purpose specified.

In testimony whereof I have hereunto set my hand in the presence of two subscribing witnesses.

JAMES B. STANWOOD.

Witnesses:

L. M. Hosea, F. L. HOSEA.

and op- 65 

